Dredge tumbler



L.. D. HOPFlELD DREDGE TUMBLER June 14', 1927..

Filed Nov. 29. 192e sheds-sheet 2 5w m \4 f \f 5 W z i Patented rJune `14, v19?'7.

LEWIS D. nOrFIELn, or NA'rOMA,v oALIFORN1A,"AssIGNOR 'ro` TAYLORfWHAR'rON j rRON &' STEEL COMPANY,

NRW JERSEY.,

DREDG A'.rUirnsLnR.

`Applicationiile. November l29, 1926. Serial No. 151,577.k

"The invention relates to dredging appara-` ytus and more particularly to the lower yftumblers for guiding kthe endless kchain of buckets in the operation of the dredge. For 5 many years the practice largely has been to construct tumblers of manganese steel rowing to the superior shockand wear-resisting qualities ofy that metal. But manganese steel has the peculiarity of peening, stretch- A ing or flowing in service and tumblers sometimes fail because of splitting of the tumbler heads dueeither to the tread breaking -loose from the spokes orthe spokes breakling away from the hubs, the action being ynot unlike .the cold rolling of themetal while Yheld upon ay mandrel. j

Hence, it isV the object ofthe inventionto prevent suoli failures by so constructing the tumbler that whilejnormally resistant it, nevertheless, is responsive to pressure tothe extent that it will absorb the usual peening and stretching and so preclude the setting up of breaking strains or stresses.

In achieving this ob.`ect,'Iy preferably pro; "2.5 vde a sectional tumbler consisting of mated tumbler heads cast as units embodying hub,

` tread'and end flange elements, the tread be-"v form, the tread being interrupted in the region of the latter to provide pockets for ing interrupted transversely so asxto absorb and thus nullify-peening or stretching.'

The nature, characteristic features and scope of the invention will more readilybe' understood from the following' description taken Min connection withthe accompanying drawings, wherein 7, r Figure l isan' end `view ofa tumblerem- D ybodying my invention.-

` Fig. 2 is a side view of the sam Fig. 3 isa longitudinal sectional view.

Fig.4 is yan end ViewV of a modified type v"10 of tumbler head.

Figo is a side view'o'f the same. Fig. 6isa sectional detail ofthe modification.

Theysectional tumbler embodies a pair of tumbler heads lwhereof` each isk integrally constituted Ofa head or flange element 6, a

tread wall 174 and a hub .Or shaft-receiving areas atan angle as y are bridged by spokes.

element lS, the tread wall and" hub being joined byspokes of which some, *indicated at 9, are Ofgeneral Yform. Over theilatter.

spokes the tread wall is interrupted byopen j or `man BRIDGE, NRW JERSEY, A CORPORATION or l slots or gaps 10 whose office it is to prevent concentrated peeningflowing orstretching- A j l" of the metal and to'accommodate Or absorb any peening or stretching that may occur. And the :Y'spokes serve to bridge the voids or spaces l0 in the tread. It willbe understood, however, that while 'theY yspokesvare my preference, theinventionmaybe availed Y kof with other forms of spokes. w Y

It likewise will be manifest lthat the provision for dispersing and absorbing peening and `stretching is capable of Aconsiderable variation. For example, instead of open slots or gaps, I may provide in the tread wall grooves yor pockets 11 spanning the spoked shown in Figs. 4L and 5,l

and in the detail, Fig.` 6.

"The tumbler sections may be secured vwith 'i l' relation'to eachother by through bolts'12.

` Having described my invention, I'claim;

having integral tread and hub elements absorbing peening and stretching.

`2. A tumbler comprising tumbler sections including tread and hub elements integrally joined by spokes, the tread 'elements having the arrangement being such that'said means '3,' A' tumbler, including constructed of manganese steel and having` integrally joined tread and hub elements, the tread elements having helio-ally disposed -slots, whereby, although normally resistant,

`l. ,A Ytumbler comprising tumbler heads 8O y means `to absorb peening and. stretching, and f tumbler heads l they are responsive to pressure to absorb cold Q A breaking strains. v

flow and thus preclude conditions tending-to In testimony whereof I atlix my signature. l

LEWIS. D. `Hofmann.v 

